Modeling, analysis and design of centrifugal force-driven transient filling flow into a circular microchannel

Recently, centrifugal pumping has been regarded as an excellent alternative control method for fluid flow inside microchannels. In this paper, we have first developed the physical modeling and carried out the analysis for the centrifugal force-driven transient filling flow into a circular microchannel. Two types of analytic solutions for the transient flow were obtained: (1) pseudostatic approximate solution and (2) exact solution. Analytic solutions include expressions for flow front advancement, detailed velocity profile and pressure distribution. The obtained analytic results show that the filling flow driven by centrifugal force is affected by two dimensionless parameters which combine fluid properties, channel geometry and processing condition of rotational speed. Effects of inertia, viscous and centrifugal forces were also discussed based on the parametric study. Furthermore, we have also successfully provided a simple and convenient analytic design tool for such microchannels, demonstrating two design application examples.     

一种新型三相流测量系统的研制

利用成熟的单相流测量仪的基本原理 ,研制了一种新的三相流在线检测仪及其系统。应用热扩散法来测量气液比 ,设计的灵巧电容探头来测量油水比 ,该仪器可适合各种不同生产条件的油田的三相流测量     

Development of a new capacitive matrix for a steering wheel's pressure distribution measurement

Pressure distribution measurements are becoming increasingly important in the automotive field for ergonomic optimization of components like seats or steering wheel. Nowadays, traditional sensors shows several drawbacks such as response variation in time, low sensitivity and high level of intrusiveness. Moreover the great difficulty of carrying out dynamical analysis in the area of interest highly limits their use. A new type of matrix, now available, promises to overcome such problems, and it has been widely tested in the automotive field. The matrix is based on a series of condensers which vary the capacity depending on the pressure applied on their surface. The high sensitivity and the chance of monitoring pressure distribution with frequency contents up to 200 Hz make this tool particularly suitable for evaluating steering wheel's goodness effectiveness in an on-road test.     

一种新型均值滤波器及在压力分布中的应用

提出了一种加入时间窗的时空自适应窗体中心加权的中值均值滤波算法,在自适应的时空滤波窗体内采用中心加权的中值选取并结合加权均值算法滤除压力分布中混合噪声。实验证明：该方法对于受椒盐噪声、高斯噪声污染比较严重的压力分布数据有较好的滤波效果,与小波、维纳滤波等其他线性滤波算法相比计算量要小得多。     

Using the method of interior points for computation of flow distribution in a hydraulic system with regulators

For hydraulic computations that take flow and pressure regulators into account, a little-known variant of the Newton method is used. Successive approximations belong to the interior of a set R specified by linear inequalities. In contrast to the base variant of the method of interior points, the Jacobian matrix is square. The solution of the problem of flow distribution is found on the boundary of R. The local convergence of the method considered is analyzed. Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 173–178, July–August, 2000.     

Development of the Kansa method for solving seepage problems using a new algorithm for the shape parameter optimization

In this research, the Kansa or Multiquadric method (MQ) has been developed for solving the seepage problems in 2D and 3D arbitrary domains. This research is the first application of this method for seepage analysis in both confined and unconfined porous media. The domain decomposition approach has been employed for applying MQ method easily in inhomogeneous and irregular complex geometries and decreasing the computational costs. For determining the optimum shape parameter that affects strongly the accuracy of MQ and other RFB methods, a new scheme that decreases drastically the computational time is introduced. The efficiency of the proposed algorithm has been examined under various radial basis functions, variations of number of interpolating points and points distribution, through a numerical example with analytical solution. Eventually, three examples including different boundary conditions are presented. Comparing results of the examples with other numerical methods indicates that the present approach has high capability and accuracy in solving seepage problems.     

Development of a fuzzy goal programming model for optimization of lead time and cost in an overlapped product development project using a Gaussian Adaptive Particle Swarm Optimization-based approach

The aim of this paper is to present a model-based methodology to estimate the optimal amount of overlapping and communication policy with a view to minimizing product development lead time and cost. In the first step of methodology, the underlying two factors are considered in order to formulate mathematically a multi-objective function for a complete product development project. To add these objectives, incommensurate in nature, a fuzzy goal programming-based approach is adopted as the second step. In order to attain the optimal solution of formulated objective function, this paper introduces a novel approach, “Gaussian Adaptive Particle Swarm Optimization” (GA-PSO), which is embedded with two beneficial attributes: (1) Gaussian probability distribution, and (2) Time-Varying Acceleration Coefficients strategy. An illustrative hypothetical example of mobile phones is detailed to demonstrate the proposed model-based methodology. Experiments are performed on an underlying example, and computational results are reported to support the efficacy of the proposed model.     

Development of a new technology product evaluation model for assessing commercialization opportunities using Delphi method and fuzzy AHP approach

As the number of new products developed by new technologies has increased, the importance of the commercialization of new technology products has become crucial to manufactures in the successful delivery of valuable new products and services. This study classified success factors for commercialization of new products and analyzed which factors should be primarily considered. Based on the literature review and Delphi method, we identified four decision areas and further prioritized the sixteen factors under a hierarchy model structured by fuzzy AHP (analytic hierarchy process) approach. The FAHP is conducted by 111 R&D and business experts working at the world’s major players in machinery industry; using the priorities of success factors derived by FAHP, we devise an example of commercialization assessment model. The paper drives the assessment initiatives of the new product development in manufactures and provides them with practical implications about the commercialization of new technology product.